2000 400ex stock carb problem

[biskitt30]

Hey guys and gals,

New to the forum here...finally I found a place where I may get the right answer.

I have a stock 2000 400ex and I'm having a slight problem with the carb. If the bike is idling (it's warmed up, this happens even if I've been on the bike for an hour straight and sitting with it at idle) and I hit the throttle about half way (not rolling on it, just hitting it to rev it) the bike sputters like it's going to stall, then when I release the throttle it goes back to an idle. If I hit the throttle quick and hold it half way it WILL stall. The same happens when I'm riding.
I've carefully taken the carb out and cleaned it, and put it back only to have the same problem. I have a K&N airfilter and I cleaned that also.
I have no idea what the problem is. Is it the carb, the jets???

[ridesa02400EX]

sounds like jetting to me but im not sure did you re jet when you put the k and n on:confused:

[biskitt30]

Unfortunatley no, when I got the bike (used) the K&N airfilter was already on it, this didnt start happening until about 3 months after I had the bike...which jet do you think it could be...and do I go bigger or smaller with the jet....I HATE CARBS:mad: :mad: :mad: :mad:

[MIKE400EX]

Check the accelerator pump/squirter, sounds like it is not working (probably clogged).

sounds like an air leak to me, like the airboot is loose from the carb???

[biskitt30]

Thanks...I may just take it out re-clean and re-jet the damm thing:mad: :mad: :mad:

although the best way to fix the problem is to just drop a match in the gas tank and then my problems will be solved:devil:

[wxmyjmy]

The boot that connects the carb to the motor cracked on my 400.
I had the same problems that you are having.
The Dealer told me that Honda changed the material that they were made of to prevent this from happening on the new ones.